Verfahren zum Messen des Kohlenstoffgehaltes eines Stahlbades bei einem Sauerstoff-oben-blasenden Konverter

In a process for tapping steel from an oxygen top-blowing converter at a predetermined carbon content involving the use of predetermined standard values of carbon content to compensate for errors in continual carbon content measurement, the flowrate of waste gas issuing from the converter in Nm3/hr [Fi], and the % volume of carbon monoxide [(CO)i] and carbon dioxide [(CO2)i] in the waste gas are continually measured, the decarburization velocity - dc/dt is calculated from the formula , the decarburizing acceleration is obtained by differentiating - dc/dt , the times of peculiar change points in the decarburizing acceleration are noted, the carbon content of the steel at the time of said changes is calculated by double integration of the decarburizing acceleration, the correct amount of decarburization (D Ci) is calculated from the formula D Ci' = S Co-(C)% x weight of molten steel, where S Co is the total carbon content of the charged material iron and (C)% is the predetermined standard value of carbon content of the steel bath corresponding to the time the above-mentioned peculiar change is detected, the amount of decarburization as D Ci is calculated by integrating the decarburizing velocity, D Ci is amended by the said correct amount of decarburization D Ci' and the steel is tapped at the exact time the carbon content of the steel reaches the predetermined value.